[help] g920w8 unknown baseband after downgrade

help..
i have g920w8 for unlock

this is version :

Code:

---

[ 8/30/2018 11:51:00 AM ] Checking hash file... OK
[ 8/30/2018 11:51:00 AM ] Searching Samsung modem... detected COM113
[ 8/30/2018 11:51:00 AM ] Reading phone info...
[ 8/30/2018 11:51:00 AM ] Model: SM-G920W8
[ 8/30/2018 11:51:00 AM ] AP version: G920W8VLS6DRA1
[ 8/30/2018 11:51:00 AM ] CSC version: G920W8OYA6DRA1
[ 8/30/2018 11:51:00 AM ] CP version: G920W8VLS6DRA1
[ 8/30/2018 11:51:00 AM ] Product code: BMC
[ 8/30/2018 11:51:00 AM ] Phone SN: RF8H111NM8W
[ 8/30/2018 11:51:00 AM ] IMEI: 351559075746883
[ 8/30/2018 11:51:00 AM ] Unique number: 1215FC2B2E5B0D04

---

then i decided to downgrade modem....

with this file

G920W8_VLU5CPI4_CP_FOR_UNLOCK.tar

and then

goodbye baseband..

now baseband is unknown

even if i flash latest firmware, full flash

still unknown baseband..

i have tried repair efs, format, flash to highest version

write cert

repair imei

reset efs

repair efs

repair network.

no luck

any suggestions?